The Mercury II broke up into several parts that can be found in the Purple Vents and Lilypad Islands biomes east of Delta Island. Unfortunately, these are also scattered across various parts of the Mercury II, a giant ship that crashed and is now beneath the waves.
The Parallel Processing Unit can be crafted once you’ve found three of its fragments. Subnautica: Below Zero guide – Parallel Processing Unit locations Note: For more information, check out our Subnautica: Below Zero guides and features hub. Here’s our guide to help you find the Parallel Processing Unit locations in Subnautica: Below Zero.
We can craft that to progress the story, but, first, we’ll need to acquire the Parallel Processing Units. After meeting Marguerit Maida in her underwater base, you’ll be able to scan a PDA that gives you the blueprint for the Test Override Module.